Benign Proximal Tubular Albuminuria due to AMN mutation: A Challenging Presentation of Imerslund-Gräsbeck Syndrome

Benign Proximal Tubular Albuminuria due to AMN mutation: A Challenging Presentation of Imerslund-Gräsbeck Syndrome | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Benign Proximal Tubular Albuminuria due to AMN mutation: A Challenging Presentation of Imerslund-Gräsbeck Syndrome Serim Pul, Neslihan Çiçek, Serçin Güven, Ceren Alavanda, Pınar Ata, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6564862/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 14 Nov, 2025 Read the published version in Pediatric Nephrology → Version 1 posted 5 You are reading this latest preprint version Abstract A 3-year-old boy presented with dark-colored urine for four months. His history was negative for infections, but he was taking oral methylcobalamin treatment for a persistent deficiency. His parents were first-degree cousins, and a female cousin had proteinuria of unknown etiology. A physical examination and laboratory examination revealed no abnormalities except for nephritic proteinuria and low levels of vitamin B12. Albumin was the main protein in the urine. Kidney biopsy showed nonspecific changes. Genetic analysis identified a homozygous pathogenic AMN gene mutation, confirming Imerslund-Grâsbeck Syndrome (IGS). Angiotensin-converting enzyme inhibitor were prescribed but discontinued due to stable protein levels. After four years, kidney function remained stable. Imerslund-Grâsbeck Syndrome is a rare autosomal recessive disorder that affects vitamin B12 and protein, particulary albumin absorption. While typically presenting with megaloblastic anemia, AMN mutations show variable phenotypes. Proteinuria is resistant to ACE inhibitors, and currently, there is no specific treatment. Periodic follow-up is required. Amnionless albuminuria cobalamin cubilin proximal tubule proteinuria Full Text Cite Share Download PDF Status: Published Journal Publication published 14 Nov, 2025 Read the published version in Pediatric Nephrology → Version 1 posted Editorial decision: Major Revisions Needed 12 May, 2025 Reviewers agreed at journal 30 Apr, 2025 Reviewers invited by journal 30 Apr, 2025 Editor assigned by journal 30 Apr, 2025 First submitted to journal 30 Apr, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6564862","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":450433679,"identity":"a8398ab3-dbd7-4bf7-9ed2-5ec6b7bc9459","order_by":0,"name":"Serim 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